典型塑料容器与汽油混合燃烧残留物的SPME-GC/MS分析

Analysis by SPME-GC/MS into the Residues from Gasoline-burned Typical Plastic Container

目的选用固相微萃取气相色谱-质谱技术(SPME-GC/MS)分析火场中常见塑料容器与汽油混合燃烧残留物,对火场中是否存在助燃剂进行判定。方法在扩散时间40min、扩散温度100℃、室温萃取的条件下,选取100μm PDMS红色萃取头,检测低密度聚乙烯和聚对苯二甲酸乙二醇酯2种塑料材质容器与汽油混合燃烧残留物的主要成分,并对火场中是否存在汽油进行定性分析。结果从两种塑料材质容器与汽油混合燃烧残留物中提取到较完整的汽油特征组分,主要包括甲苯、二甲基苯、三甲基苯、四甲基苯、五甲基苯、萘、甲基萘及茚满类化合物。结论固相微萃取气相色谱-质谱检测方法灵敏度高、影响因素较少,能够满足对火场残留物中汽油特征组分的检测要求。

Objective To determine the existence of accelerant in fire scene by solid-phase micro-extraction coupling gas chromatography mass spectrometry(SPME-GC/MS) through analyzing the residues from burning plastic container with gasoline. Methods Under the diffusion time of 40 min, diffusion temperature of 100°C and extraction at room temperature, the 100μm PDMS red fiber-filter was selected to extract the residual components from gasoline burning the main ingredients of plastic container: low-density polyethylene(LDPE) and polyethylene terephthalate(PET). SPME-GC/MS was conducted of qualitative analysis into the extracted residues while testing the presence of gasoline in the fire scene. Results The characteristic components of gasoline were detected out of the extracted residues from gasoline combusting two types(LDPE and/or PET) of plastic container, with evident demonstration of toluene, dimethylbenzene, trimethylbenzene, tetramethylbenzene, pentamethylbenzene, naphthalene, methylnaphthalene, indene, and their respective present isomers or homologues. Conclusions The SPME-GC/MS detecting approach has high sensitivity and few influential factors, capable of meeting the requirements to detect characteristic components of gasoline from fired residues.